1. Field of the Invention
This invention relates to photographic cameras with controls that automatically adjust the camera aperture during daylight or available light operation as well as when the camera operates with a flash unit.
2. Description of the Prior Art
In known camera-flash systems, a light control circuit automatically adjusts the light output of an automatic flash to produce a proper exposure for a specified aperture and a particular film sensitivity. Therefore, it is necessary to preset the diaphragm of an interchangeable lens at this specific aperture value for flash operation. Hitherto, it was necessary to preset the aperture of the interchangeable lens manually for automatic flash operation. Conventional cameras with automatic exposure controls cannot automatically be set for flash operation. Thus, photographers often forget to set the aperture of such cameras when operating with flash because they are accustomed to thinking of the camera as having an automatic exposure control.
In order to make an interchangeable lens camera automatic under all types of conditions, it is necessary to enter certain information. For example, in automatic exposure control cameras having diaphragm controls with shutter priority and a totally open light measuring system, it is necessary to enter the film sensitivity, the shutter speed, and the maximum F value of the lens being used, into the diaphragm control. Of the above, the film sensitivity must be entered into the diaphragm control even when operating within an electronic flash that adjusts its light automatically.
It is an object of the invention to improve cameras of this type. It is another object of the invention to overcome these problems.